What is the purpose of these lines within the assignment operator?

while $(!$empty$())$

pop$()$;

topindex $=$ new top;

a$.$ To print the contents of the stack to the console.

b$.$ To push a new node onto the stack.

Oc$.$ To create a temporary copy of the stack for reference.

Od$.$ To clear the existing stack before assigning new values, ensuring a deep copy